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31.
LI Jun-Linga① GU Juna QIU Guang-Minb a 《结构化学》2006,25(5):589-593
1 INTRODUCTION Since the introduction of QSAR by Hansch and Fujita in 1964, Deutsch and Hansch have quickly used it in the study of nitrophenylamine sweet reagents. They found good correlation between their distribution coefficients in octanol/water system and sweetness degree. Subsequently, they detected that vibration of aroma-substituent compounds has so- mething to do with sweetness. Henceforth, statistic correlations between structure and sweetness ofseries compounds have been inv… 相似文献
32.
HOU Xiao-Mina b CHEN Ming-Huanga② XIE Jie-Mingc YE Xiao-Minga ZHAO Geng-Xianga b YANG Fenga b CHEN Li-Qingd HUANG Ming-Donga a 《结构化学》2006,25(9):1035-1038
1 INTRODUCTION The ribosome-inactivating proteins (RIPs) are RNA N-glycosidases[1, 2] which inactivate ribosomes by cleaving a single N–C glycosidic bond between adenine and ribose at A4324 in the 28s rRNA of rat. Because of the removal of one adenine from rRNA, elongation factorⅡ(EF-2) can not bind to the 60S subunit, so RIPs can arrest protein synthesis. RIPs can be classified into three types based on the struc- tures of genes and mature proteins[3]. Type 1 RIPs with molec… 相似文献
33.
ZHAO Hui-Minga YUAN Li-Xiaa YANG Guo-Yinga SUN De-Shengb WANG Zun-Yaoa② CHI Qing-Qinga a 《结构化学》2006,25(10):1280-1286
1 INTRODUCTION Interhalogen compounds have played an impor- tant role in environment and chemical engineering production. During the course of ozone exhaustion induced by sunlight in polar region, Br2, BrCl and HOBr are all precursors of Br atom[1]. Lately, scien- tists have detected that the content of BrCl in polar region sunlight was 35 ppt, larger than that of Br2 (25 ppt). Previous studies suggested that the con- centration of BrCl and O3 exhibits obvious negative correlation: w… 相似文献
34.
Synthesis and Crystal Structural Characterization of a Thiosemicarbazone Derived from 4-Acylpyrazolone 总被引:1,自引:0,他引:1
LIU Guang-Feia LIU Langa HU Xina JIA Dian-Zenga② YU Kai-Beib a 《结构化学》2006,25(10):1233-1237
1 INTRODUCTION Pyrazol-5-one derivatives form an important class of organic compounds due to their structural che- mistry and biological activities as analgesic, antipy- retic, anti-inflammatory and hyperglycemic agents[1~4]. Even the simplest pyrazol-5-one derivatives like antipyrine and amidopyrine are widely used in anal- gesic medicine[5, 6]. On the other hand, thiosemicar- bazones, especially heterocyclic thiosemicarbazones, have been the subject of extensive investigations be- cause… 相似文献
35.
The title compound belongs to monoclinic,space group C2/c with a=5.2694(1),b=12.6659(4),c=19.4108(2) ,β=91.504(2)°,V=1295.06(5) 3,Z=4 and Dc=5.599 g/cm3. The structure of BaGd2(MoO4)4 contains a MoO4 tetrahedron,a distorted GdO8 polyhedron,and Ba2+ ions in a tenfold coordination. The GdO8 polyhedra are linked together through edge-sharing to give a two-dimensional Gd layer. The MoO4 tetrahedra connected to the Gd atoms are capped up and down the Gd layer through common oxygen apices,thus forming a new Gd-Mo layer. Finally,the Gd-Mo layers are held together through bridging BaO10 polyhedra to form a three-dimensional framework. Since the Ba-μ3-O bond has a large average distance of 2.888 ,this structural characteristic will result in a cleavage along the (001) plane. 相似文献
36.
1 INTRODUCTION Since the discovery of carbon nanotubes (CNTs) by S. Iijima[1] in 1991 as a quasi-one-dimensional nano-material, extensive attention has been paid to CNTs due to their special electric conductivity, me- chanical properties and potential applications in molecular device, complex material and so on. The structures of CNTs could be described as graphite sheet with planar hexagonal network structure cur- ling into a tube having the diameter of only several nanometers. In t… 相似文献
37.
1 INTRODUCTION Late-transition metal complexes as catalysts for ethylene oligomerization and polymerization have become an intense research subject[1]. Nickel com- plexes are in hot point due to the significant achieve- ments of academic research[2, 3] and industrial appli- cations[4, 5]. The nickel complexes with bidentate [P,O] ligands were industrialized as the SHOP pro- cess for α-olefins[4]. It is supposed that late transition metal complexes have a strong propensity of under- goi… 相似文献
38.
Yong Nian Ni a b Xue Zhi Zhong a a Department of Chemistry Nanchang University Nanchang China b The Key Laboratory of Food Science of MOE Nanchang University Nanchang China 《中国化学快报》2007,(5)
The binding characteristics of neutral red (NR) with DNA were investigated by fluorescence spectrometry. Chemometrics approach as singular value decomposition (SVD) was used to evaluate the number of spectral species in the drug-DNA binding process, and then the intrinsic binding constant of 1.6 104 in base pairs and the binding site number of 0.97 were obtained from the Scatchard plot. 相似文献
39.
40.
Wei-qiang Zhou~ 《高分子科学》2008,(1):81-90
The copolymerization of dibenzofuran(DBF)and 3-methylthiophene(MET)was successfully achieved electrochemically by direct anodic oxidation of the monomer mixtures in boron trifluoride diethyl etherate.The effects of applied polymerization potential and the monomer concentration ratios on the copolymerization were investigated by linear sweep voltammetry and cyclic voltammetry(CV).The structure of copolymer films were investigated by UV-Vis,infrared spectroscopy,thermal analysis.As-formed novel copolymers ... 相似文献